The goal of this research is to increase understanding of the psychosocial factors involved in human fertility control. More specifically, it aims to develop predictive indicators of probable success or failure in contraceptive planning. It will investigate the motivation and personality of successful and unsuccessful contraceptors, and the origin and nature of their sexual attitudes and behavior. In particular, it will focus on their attitudes toward family planning and their resistances and reactions to various contraceptive practices. The methodology involves a longitudinal study of clinic clients receiving contraceptive counseling at a Planned Parenthood Association clinic. Applicants will be interviewed and given several different behavioral, personality, and attitude measures, some of which have shown great promise in pilot studies. After a period of at least one year, the criterion of contraceptive failure or success will be established and the predictive validity of the various measures for indicating the likelihood of contraceptive failure will be determined. Later stages of this project will include a replication study on a sample of clients from a different contraceptive clinic, in order to test the generality of its major results. In addition, related studies of non-clinic populations will be conducted to provide comparative normative data on the successful predictor measures. The results of this diagnostic research on the characteristics of successful and unsuccessful contraceptors should have important implications for developing counseling or intervention programs designed to minimize the number of contraceptive failures, with their attendant heavy social costs and deep personal anguish.